Average intake flow up to .300" lift with stock cams = 93.216 cfmAverage intake flow up to .350" lift with Ace Magnum Cams = 103.115 cfmAverage flow and peak flow would increase further if ratio roller rockers were installed.All flow at all lifts would also increase with porting and valve job.Obviously if lifts go over .350" the exhaust port will need to be ported/cured of the restriction causing it to back up at higher lifts.

Flow rates are not too much different than the stock Iron Barrel head. Similar modifications of porting, cams and/or ratio rockers, valve spring upgrades, would be recommended to bring it up to Fireball standards. For a reference, the Fireball intake flows 195 cfm at .350" lift, and averages 121.75 cfm up to .350" lift.With big roller rockers on this head, and a good porting and bigger valves, it could exceed the Fireball flow, and get into the racing head territory pretty well. That's not necessary for most street applications, but the options are there.

This is great data and information. Thanks Ace for sharing the flow rates of the AVL. Lots of provoking thoughts right now.

Did you and 2CV agree to what's going to be done? New springs I've read, larger exhaust port or value upgrade? I'm seriously considering sending mine off to you to get the most out of bw's s cams (street only).

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Suppose I were an idiot, and suppose I were a member of Congress; but I repeat myself. ... Mark Twain2006 AVL Electra

This is great data and information. Thanks Ace for sharing the flow rates of the AVL. Lots of provoking thoughts right now.

Did you and 2CV agree to what's going to be done? New springs I've read, larger exhaust port or value upgrade? I'm seriously considering sending mine off to you to get the most out of bw's s cams (street only).

Yes, the mods will be essentially like we do with the Fireball head on the Iron Barrel, adapted to the AVL head requirements.No special cams or rockers, so the lift will remain the same as stock.No changes to the piston.

Ace, what general up grades ( if any) do you recommend for lower end of the AVL with Fire Ball?

Well, it depends on how well the factory did with each particular bike. In theory, the AVL supposedly has all the necessary upgrades already in it. It has the roller bearing on the big end of a steel con rod, and high output oil pumps, and an alloy barrel as standard equipment. Where the questions arise with the AVL, are whether they put it all together well enough to ensure that it will hold up.

If you would like to know what I think might be the places where stress failures might occur on a higher output AVL, I think it would be in the bearings. The bearings are the same as the Iron Barrel engine, which would be okay if they were very high quality units like we put in with rhe Fireball. I think it's pretty clear that the factory opts for bearings that are quite a bit lower in cost, and so they often don't take any added stress very well. With the AVL roller big end bearing, it's just like the UCE. Depending whether they got the hardening correct on the big end eye of the con rod, it might hold up fine if it also got the proper clearance during assembly. If it didn't get good heat treating and proper clearance, then it won't. We can't say what will happen because of variance in manufacturing.

For an AVL owner looking g to upgrade and do things to try to overcome these potential issues, I would say to get a good set of bearings like we use, and get an outer race installed in the con rod which is precision honed to proper clearance for a new top quality roller bearing like an Alpha bearing. Rebuild the crank with precise truing to minimize vibration.These are the things we do with the Fireball. With an iron barrel bike, it's obviously needed to change all the bottom end parts out before trying to upgrade the power. With the AVL, it is less obvious, and it may, or may not, be necessary for a mild/moderate power increase. For a big power increase, I would go ahead and do a full upgrade to the bottom end in advance.

With the behavior of bearings in failure mode, they give plenty of warning with knocks and other bad sounds when the begin failing. So it is conceivably okay to try the power mods on the stock bottom end, and if it holds up to it, then fine. If it starts knocking after maybe 1500 miles, then it wasn't okay, and you need to open it up and do the bottom end work to it. Otherwise, it could all be done at first as a preventive measure. We have no way of knowing which engines will be able to handle the power upgrades the best. It was determined at the time of the bike's manufacture. Lower power upgrades are more likely to do okay without bottom end mods than big power upgrades would be. If you do the bottom end work first, then it will handle any power upgrade level that you might want to choose.These choices are made by each owner. The above info can be a guideline. I can't say for certain what engine can withstand what level of power in factory form. It is very much a "luck of the draw" situation of how well the factory did on your specific machine.

Should I order Pilots from #30 to #40 (3) & Mains from #195 to #240 (6)?

You might want pilot jets 27.5, 30, a 32.5, and a 35, maybe. Just for some potentials for tuning adjustments in unusual circumstances of elevation or temperature.I think the mains might be good to have 180, 185, 190, 195, 200. It would be very unusual to need over 200 main jet.The needle jets are probably more critical for average riding. They control the cruising range of the engine, so you feel them most, and they affect the response and fuel economy in the most used rpm range.I would get P2, P4, P6, P8 needle jets.And I would get a 6DP17 needle, for getting leaner adjustments if you were to go high up in elevation in the summer, ever.

In the peak heat of the summer, you need leaner jetting.In the dead cold of winter, you need richer jetting.In the shoulder seasons, you are somewhere in the middle.

Went to the jap bike store yesterday & ordered the Sudco throttle cable for the TM-32 & a 90 degree cable adjuster for the top. I don't want any sharp bends.

This morning I took the switch assembly off (2 screws) that houses the throttle cable rotator & removed that. I left the cable in place. I'm hoping I can snake the new one through using the old one to pull it through with. Probably won't work & I'll end up pulling the headlight out.Oh, well Don't want to screw up a connector in the rat's nest.

I noticed on the bottom half of the switch assembly there's a threaded hole with nothing in it. Does any know? It looks like it could have been some kind of primitive cruise control on another bike.

.......I noticed on the bottom half of the switch assembly there's a threaded hole with nothing in it. Does any know? It looks like it could have been some kind of primitive cruise control on another bike.......

Not really Cruise Control. There's supposed to be a set screw in there, more of a tensioner on the actual throttle grip housing. I always have mine set so it doesn't make any contact as I like my throttle to "snap" back closed when I let go of it. I would try and put a screw back in there if for nothing else to keep dirt and grime out of there.

Not really Cruise Control. There's supposed to be a set screw in there, more of a tensioner on the actual throttle grip housing. I always have mine set so it doesn't make any contact as I like my throttle to "snap" back closed when I let go of it. I would try and put a screw back in there if for nothing else to keep dirt and grime out of there.

Scottie J

I agree with you; I want no hesitation on returning to idle. Been there, done that.

I have maybe 16 pounds of assorted machine screws down there in coffee cans. Waddayoo wanna bet I never find a screw that'll thread into that hole?

That does give one the idea of making a basic cruise control, or for better terms, throttle holding latch.Various notches on your bars next to the throttle and a small latch on the thing itself? Lock into place and hold throttle open?Obviously a quick releasing system

That does give one the idea of making a basic cruise control, or for better terms, throttle holding latch.Various notches on your bars next to the throttle and a small latch on the thing itself? Lock into place and hold throttle open?Obviously a quick releasing system

Not much point in that when you can buy ACTUAL cruise control for $35. Though I must emphasize that these throttle lock cruise controls are more for fucking around than using for cruise control. They are really only worth a crap if you're driving through Nebraska mile upon mile of flat road. They work good for giving your throttle hand a rest on long rides too, but that's about it.

That does give one the idea of making a basic cruise control, or for better terms, throttle holding latch.Various notches on your bars next to the throttle and a small latch on the thing itself? Lock into place and hold throttle open?Obviously a quick releasing system

Speaking only for myself, of course, I have no use for cruise control on the Enfield. I just don't do that kind of riding any more. I don't think I've cruised in any one gear without a throttle change for more than 15 minutes since the Summer of 2010 when I first got on the thing. The Enfield's not exactly a marathon long distance runner at full throttle til the next fuel stop.

Other bikes built for that job - yes.

I do use it in my wife's car on the way to Home Depot, but that's about my only experience with cruise control.

Tooseevee...just did my throttle cable, noticed the same thing....I have a '90 k75 bmw that uses a primitive throttle lock screw right there...guess we didn't get ours. The throttle cable went in like butter after I figured it out, Put the ball less end thru the throttle hole then slip the slit stepped collet over the bear cable. Cable easily slides thru the dedicated cable hole in the nacelle Matt